Electrical Problem on a '68
Thread Starter
Drifting
Joined: Mar 2001
Posts: 1,600
Likes: 0
From: Valencia (near LA) CA
Electrical Problem on a '68
My car is eating regulators!
The Alternator is an aftermarket unit that has been rebuilt to produce 94 amps. It is the external regulator type that is proper for a '68.
I figured I needed more amps to power the Spal fans and 500w stereo.
Is it possible that the stock regulator can't handle the more powerful alternator?
Could there be a short in the igniton switch that is ruining the regulators?
This is the second one to go in the last 5 months.
The car is in the shop now. They replaced the last one under waranty. But for this one I think they want to get to the core of the problem. That equals LOTS of hours!!$$$
Any suggestions I give could vastly shorten that time.
thanks,
~Jay
The Alternator is an aftermarket unit that has been rebuilt to produce 94 amps. It is the external regulator type that is proper for a '68.
I figured I needed more amps to power the Spal fans and 500w stereo.
Is it possible that the stock regulator can't handle the more powerful alternator?
Could there be a short in the igniton switch that is ruining the regulators?
This is the second one to go in the last 5 months.
The car is in the shop now. They replaced the last one under waranty. But for this one I think they want to get to the core of the problem. That equals LOTS of hours!!$$$
Any suggestions I give could vastly shorten that time.
thanks,
~Jay
Melting Slicks
Joined: Oct 2002
Posts: 2,865
Likes: 1
From: I may be getting old but I refuse to grow up
Re: Electrical Problem on a '68 (Jay M)
What's happening to the regulators? from what I remember of external regulators they're a set of relays (voltage and current).
Steve :steering:
Steve :steering:
Drifting
Joined: Nov 2002
Posts: 1,665
Likes: 1
From: Ontario
Re: Electrical Problem on a '68 (Jay M)
I would say upgrade your regulator. Sounds like you need the upgraded alternator to run all your electrical devices, but its not that the alternator is too powerfull for the regulator, its that the regulator can't handle the amount of current drawn by your devices. :cheers:
Melting Slicks
Joined: Oct 2002
Posts: 2,865
Likes: 1
From: I may be getting old but I refuse to grow up
Re: Electrical Problem on a '68 (Boofers)
Regulator only controls voltage, there isn't a current relay on an altenator.
Here is how it is described in one of my apprentice training manuals
When the voltage increases to the value for which the regulator has been set, the magnetism of the regulator winding is strong enough to pull the regulator armeture down. This separates the set of contacts and inserts resistance in the alternator field circuit. The field strength is reduced and the voltage drops. As the voltage drops the magnetic field in the regulator winding is weakend. Now the armature is released by the regulator winding and it moves up closing the contacts. this is repeated very rapidly, preventing excessive voltage at low to mid RPM's At higher RPM's the field winding is grounded at both ends.
The electronic regulator is similar but with transistors to switch the field winding circuit.
Steve :steering:
[Modified by stpman, 5:37 PM 4/1/2004]
Here is how it is described in one of my apprentice training manuals
When the voltage increases to the value for which the regulator has been set, the magnetism of the regulator winding is strong enough to pull the regulator armeture down. This separates the set of contacts and inserts resistance in the alternator field circuit. The field strength is reduced and the voltage drops. As the voltage drops the magnetic field in the regulator winding is weakend. Now the armature is released by the regulator winding and it moves up closing the contacts. this is repeated very rapidly, preventing excessive voltage at low to mid RPM's At higher RPM's the field winding is grounded at both ends.
The electronic regulator is similar but with transistors to switch the field winding circuit.
Steve :steering:
[Modified by stpman, 5:37 PM 4/1/2004]
Drifting
Joined: Nov 2002
Posts: 1,665
Likes: 1
From: Ontario
Re: Electrical Problem on a '68 (stpman)
Good explanation of how the regulator works. I was wrong about the regulator not being able to handle the amount of current your car draws. :bb I thought the current travelled through the regulator to the rest of the car, most electronic voltage regulators do carry the current. Alternator regulators are isolated from the main load.
I still say upgrade your regulator, an electronic one would be better. The higher current output of your alternator means that its output voltage will fluctuate faster. Sounds to me like the reason your regulator is failing is that it is being switched on and off at a speed it was not originally intended for. An electronic regulator will be able to handle higher switching speeds.
I still say upgrade your regulator, an electronic one would be better. The higher current output of your alternator means that its output voltage will fluctuate faster. Sounds to me like the reason your regulator is failing is that it is being switched on and off at a speed it was not originally intended for. An electronic regulator will be able to handle higher switching speeds.
Thread Starter
Drifting
Joined: Mar 2001
Posts: 1,600
Likes: 0
From: Valencia (near LA) CA
Re: Electrical Problem on a '68 (Boofers)
ok...
Here were the symtoms:
car was undercharging, then hard to start,
I got it started, then it appeared to be overcharging,
I heard a high pitched whine when I accelerated
I opened the hood and smelled something burning
To my surpprise, Here is what the guys at the shop found:
The power steering pump belt was loose. Because of the hydroboost stepping on the brake would cause the belt to slip, and thus not turn the alt.
The belt was so loose that it was rubbing on something- hence the smell and sound.
I couldn't believe how much better the car drives now! The brakes and steering feel incredibly diferent.. like a new car. I gues I didn't notice the gradual degredation.
Best of all the shop didn't let me pay them. They spent two hours working on it until they found the 2 minute fix.
Thanks for all the info.... It's amazing how you can assume so much. I thought for sure the regulator was shot. I'm glad i was wrong :)
~Jay
Here were the symtoms:
car was undercharging, then hard to start,
I got it started, then it appeared to be overcharging,
I heard a high pitched whine when I accelerated
I opened the hood and smelled something burning
To my surpprise, Here is what the guys at the shop found:
The power steering pump belt was loose. Because of the hydroboost stepping on the brake would cause the belt to slip, and thus not turn the alt.
The belt was so loose that it was rubbing on something- hence the smell and sound.
I couldn't believe how much better the car drives now! The brakes and steering feel incredibly diferent.. like a new car. I gues I didn't notice the gradual degredation.
Best of all the shop didn't let me pay them. They spent two hours working on it until they found the 2 minute fix.
Thanks for all the info.... It's amazing how you can assume so much. I thought for sure the regulator was shot. I'm glad i was wrong :)
~Jay
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